Can't fix my CEL!

[lukejf04]

Hey all,
New to this forum, but have been reading it for a while. Just recently bought a used 1999 1500 a few months ago and the last month or so I have been chasing a CEL. I pulled up P0132 and P0135 when I scanned it. I replaced the front O2 sensor with a brand new one and also cleaned out my throttle body (which looks clean so no plenum gasket problems, thank god!). But just this morning my CEL popped back on and sure enough its the exact same codes. What am I doing wrong here??

Thanks so much for the help!

 

[jf5.9]

a clean throttle body is not a guarantee of a good plenum gasket. My throttle body was fairly clean when I had to replace mine. I would read over the plenum thread and double check yours.

 

[dodge dude94]

Both of those codes are for the pre-cat O2 sensor.
What brand did you install?

 

[Johnn123]

Oh man these codes are bad news. Ive been fighting them for over a year now and still cant get them to clear. I thought I cleared them back in November, replaced thermostat and they disapeared for a good 500 kms but then they were back. Ive seen it can be cleared by cleaning the connectors off, might try some electrical contact cleaner in them.

Clean TB has nothing to do with the plenum, head over to the Engines and Performance section and read the plenum sticky.

 

[lukejf04]

Dodge dude 94, the shop I took it too installed a Bosch sensor with a 20 inch wiring unit. Thought that was a bit long but he said it would not reach without it...

And yeah I will check out that sticky for sure. I guess my understanding was a little off... Could a blown plenum gasket cause these codes? Or are we talking about two separate things here?

 

[dodge dude94]

Most trucks hate the Bosch sensors, factory is NTK.

The blown plenum will burn oil which fouls O2 sensors and plugs cats.

 

[lukejf04]

Will it throw codes back up less than 24 hours later though? I had the O2 sensor done yesterday around 100pm and this morning at 600am it was already back on. A blown plenum shouldnt foul up the sensors that fast should it?

 

[dodge dude94]

The plenum won't foul them that quickly, no, however the PCM will toss a code that quickly as the pre-cat O2 sensor is what determines fuel mixtures.

 

[lukejf04]

So what is my next step here? Throw an NTK sensor on and that should help? Or am I looking at something completely different now? I need to pass emissions soon and its kinda been bugging me now

 

[dodge dude94]

Putting an NTK in is a start. Were both sensors replaced?

 

[lukejf04]

Yes, I had the back sensor done about a month ago when I had some exhaust work done. At the time they said my front sensor was fine so they reused it, but now within the last month I have had both replaced.

Also looked at the sticky on the plenum gasket and it could be my problem as I had to replace my cat just a month ago too. But that doesn't explain the codes coming back for the O2 sensor so fast.

I'll try throwing a NTK on and see if that helps.

 

[Johnn123]

This misconception on Bosch sensors needs to end. I know I used to preach otherwise but realistically wheres the proof they dont work? Nowhere Ive seen. Someone please link me to proof if there is. I would love to be proven wrong. Besides how do we know the ones that do have issues arent bad from the factory? NTK's can come bad from the factory too. 24 hours is the norm for mine and I have NTKs so I dont think brand is the problem. Something else causes this. I highly doubt an NTK will fix it the code thats not the issue. Check your wiring harness for any frays/broken wires near the O2's, clean the connectors up and check the PCM connections. I am going to try a bosch for my next sensor and see what happens.

 

[dodge dude94]

Quit being logical, John.

You should know I'm the first person to bash Bosch O2 sensors.

 

[Johnn123]

Quit being logical, John.

You should know I'm the first person to bash Bosch O2 sensors.

I LOVE being logical

I know you are lol, but Ive come to the conclusion the evidence to support that claim is insufficient so I wont blame them as bad sensors.

 

[dodge dude94]

I LOVE being logical

I know you are lol, but Ive come to the conclusion the evidence to support that claim is insufficient so I wont blame them as bad sensors.

Just remember, NTK is the most used OE O2 sensor in these trucks, from the factory. Them and Denso. Bosch was never used as OE, which is why guys have had problems with them before.

 

[Johnn123]

Just remember, NTK is the most used OE O2 sensor in these trucks, from the factory. Them and Denso. Bosch was never used as OE, which is why guys have had problems with them before.

Most used because its OEM. Lol. Most people replace with the OEM part. Might be the case but theres nothing to prove that was the issue and nothing to prove it was a bad sensor from the factory. Im not sure really. I just dont think theres enough evidence there to jump to that conclusion.

edit: We should prob take this to pm so we dont derail this thread lol.

 

[dodge dude94]

Most used because its OEM. Lol. Most people replace with the OEM part. Might be the case but theres nothing to prove that was the issue and nothing to prove it was a bad sensor from the factory. Im not sure really. I just dont think theres enough evidence there to jump to that conclusion.

edit: We should prob take this to pm so we dont derail this thread lol.

I don't think we're derailing. It IS O2 sensor talk after all.


Unfortunately, we can't get 10, 2nd gen guys to do a test on this.